Film bag

ABSTRACT

The disclosure relates to a multilayer film bag ( 1 ) for storing food products, in particular beverage concentrates, with a bag wall ( 7 ) including at least one external wall ( 10 ), one barrier layer ( 9 ), for example for oxygen and/or light, and one internal wall ( 8 ). The multilayer film bag includes a predetermined breaking point ( 2 ) in the film bag wall which tears open under pressure, for example at pressures above 100 kPa, 150 kPa, 200 kPa, 400 kPa or 500 kPa without any parts of the film bag tearing off.

FIELD OF THE INVENTION

The invention relates to a film bag for storing products, in particular food products, such as beverage concentrates which are mixed with water (still or enriched with CO2) as soft drink. The invention furthermore also relates to a method of draining a film bag.

BACKGROUND

Multilayer film bags are known, for example, from EP0473517, where a tear-off seam is worked into the film bag under the action of laser, so that it can be more easily opened by a user. However, opening the film bags described in EP0473517 by machines is cumbersome.

In U.S. Pat. No. 642,068S, a foil impermeable to oxygen is welded onto a container by means of thermal processes after the product has been placed into it. However, the container itself does not include any oxygen barrier. The manufacture, filling and sealing of the container requires several process steps and is therefore complicated and expensive. The viscosity of the products is restricted to liquid and free-flowing products as these can be easily flushed or pressed out of the container. For this, complex apparatuses are required which then mix the product, for example, with water into the beverage. An increased germ contamination can also occur here as the product flows over the unsterile edge of the container.

It is thus an object of the present disclosure to provide a film bag, a method, and a device, so that it becomes possible to drain a shapeless film bag nearly without leaving any residues, and wherein the film bag additionally includes barriers for light and/or oxygen and is microbiologically safe to handle.

SUMMARY

This is achieved according to some aspects by a multilayer film bag according to claim 1, a method according to claim 11, and a device according to claim 16. Advantageous embodiments and further developments are the subject matter of the sub-claims.

The multilayer film bag disclosed herein with a bag wall including at least one external wall, one barrier layer, for example for oxygen and/or light, and one internal wall includes a weakening in the film bag wall which tears open at a predetermined breaking point in a controlled manner under the action of pressure, for example at pressures above 100 kPa, 150 kPa, 200 kPa, 400 kPa or 500 kPa, i.e. in particular e.g. without any parts of the film bag getting detached in the process.

This has the advantage that the film bag can be easily and safely emptied mechanically nearly without leaving any residues independent of its shape and that no detached parts of the film bag affect and optionally microbiologically contaminate subsequent method and product treatment steps.

The weakening as predetermined breaking point, which is advantageously centrically attached on an external wall side of the film bag and is produced, for example, under the action of light, can have an extension which is advantageously smaller than one half, one third, or one fourth of the extension of the external wall side on which the predetermined breaking point is located. A position of the predetermined breaking point centered on the external wall of the film bag can facilitate the mechanical draining of the film bag under the action of pressure as it can thus be better ensured, for example, that the weakening or the predetermined breaking point, respectively, is located above the outlet opening of the draining chamber independent of rotations of the film bag in one plane. However, non-centered positions of the predetermined breaking point on the external wall side of the film bag are also conceivable.

Advantageously, the film bag can have a rectangular shape and comprise at least one weld seam for closing the film bag after it has been filled, the weld seam/weld seams being resistant to pressures above the aforementioned pressure ranges leading to an opening of the predetermined breaking point.

Moreover, the predetermined breaking point can include a cover, for example a protective foil, against contamination and soiling which can be fixed by an adhesive, and a cover tongue by which the cover can be removed manually or mechanically before draining.

It is furthermore advantageous for the depth of the predetermined breaking point in the external wall of the film bag not to reach deeper than to the barrier layer. This advantageously ensures that the product stored in the film bag is not affected by light or oxygen which could penetrate into the region of the predetermined breaking point before opening.

The film bag can preferably have height dimensions that are smaller than the length and width dimensions.

Equally, the film bag can be provided with a position detection mark. This can facilitate the verification of the correct position and orientation of the film bag in a draining device.

Under the action of pressure, the predetermined breaking point can advantageously bulge outwards and form an outward shape before it is torn open/opened. The film bag can then be drained more easily and nearly completely after it has been torn open under relieved pressure without leaving any residues.

Moreover, it is advantageously possible for the bag wall to bulge with the predetermined breaking point during draining such that the predetermined breaking point closes after draining in a drip-tight manner.

Film bags in which liquids having a viscosity of >100 mPa s are stored can thus be drained largely without leaving any residues in accordance with the invention.

In a further advantageous embodiment of the invention, it is conceivable that a small quantity of gas, for example an air bubble, is located in the flat-lying container at the side wall located above and opposite the predetermined breaking point, and that it flushes the outlet opening of the predetermined breaking point free from any product when the film bag is being drained.

According to the disclosure, draining the film bag can be effected by means of a draining device as follows.

In the process, the film bag is placed into a draining chamber whose geometrical dimensions can preferably be adapted, as concerns its draining chamber width and draining chamber length, to the film bag width and film bag height, and pressure is exerted onto the film bag by means of a pressing device, by the pressing device lowering down, for example, onto the film bag, so that a bulging is formed which, when the film bag wall is overexpanded on the side of the predetermined breaking point, opens the predetermined breaking point, for example in its center, and the film bag is drained nearly without leaving any residues.

Additionally, when pressure is applied, it can be distributed uniformly across the surface of the film bag by means of a compressible cushion at the pressing device.

When the pressing device is lowered, the cushion of the pressing device can advantageously expand into the bulge of the film bag wall because no resistance is formed in the region of the outlet opening of the draining chamber, and it can press out the product stored in the film bag nearly completely.

It is also possible to flush the product residues out of the film bag when the film bag is being drained by means of an air bubble in the film bag which is located at the uppermost point of the bag height in the draining position.

It is furthermore possible to drain the film bag into/above a product chamber and to flush the product chamber after the film bag has been drained, for example with mixing water (still or blended with CO2).

The attached figures show by way of example

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a three-dimensional or isometric view of an exemplary design of a film bag.

FIG. 1 b is a plan view onto the film bag of FIG. 1 a.

FIG. 1 c is a cross-section through the film bag wall.

FIG. 1 d is a plan view onto the predetermined breaking-points in different shapes.

FIG. 2 is a three-dimensional or isometric view of a cover.

FIG. 3 a is a side view as a section of a draining device with an inserted film bag.

FIG. 3 b is a cross-section of the snapshot of a step in the process of draining the film bag.

FIG. 3 c is a cross-section of the snapshot of the flushing step.

FIG. 4 is a three-dimensional or isometric view of a drained film bag.

FIG. 5 is a side view as a section in an exploded view of a draining device.

DETAILED DESCRIPTION

FIG. 1 a shows a three-dimensional view of an exemplary multilayer film bag 1 with a predetermined breaking point 2 produced under the action of light. Here, the height 3 a of the film bag 1 is smaller than the length 3 b and the width 3 c.

FIG. 1 b by way of example shows a view of the film bag side of the film bag 1 of FIG. 1 a on which the predetermined breaking point 2 is located. By way of example, the predetermined breaking point 2 is located at the bottom side 6 of the film bag 1.

In this example, the length 3 b and the width 3 c of the container have the same edge lengths, however, the geometric shape of the film bag 1 can also be designed in another shape, e.g. as rectangle, polygon or circular shape. The positioning of the weakening of the predetermined breaking point 2 on the bottom side 6 of the container 1 can advantageously be located in the diagonal position 4 and/or advantageously in the center 5 of the film bag 1. However, other positions of the weakening of the predetermined breaking point 2 which are neither centered nor located on a diagonal line are also conceivable. To be able to ensure that the operator/a machine has placed the container 1 the right way round in the draining chamber 24, independent of rotations with respect to the plane of insertion, the film bag 1 can be provided with a position detection mark 2 a as marking. This position detection mark 2 a can be designed, for example, as notch in the bag wall, as a hole, as a painting, as printing, as a sticker, etc.

FIG. 1 c shows a view as a section through a multilayer film bag wall 7. The internal wall layer 8 of the film bag wall can advantageously consist of thermoplastics, e.g. PE, PP, PET, PA, or else of natural rubber or rubber, and be weldable. Preferably, the extensibility at a low compressive force is >1 Newton, however <100 Newton, preferably 20 Newton.

A central barrier layer 9 functions as protection of the product 33 for shielding off luminous radiation and/or gas diffusion, for example oxygen diffusion, and can consist, for example, of aluminum.

Like the internal wall layer 8, the external wall layer 10 of the film bag wall 7 can also advantageously consist of thermoplastics, e.g. PE, PP, PET, PA, or else of natural rubber or rubber, and have an extensibility at a low compressive force of >1 Newton, however <100 Newton, preferably 20 Newton.

In an exemplary embodiment, the film bag 1 can have an internal wall layer 8 of 40 μm PE, a barrier layer 9 of 7 μm aluminum, and an external wall layer 10 of 12 μm PET. All these thickness specifications can deviate by 10% or 20% or even more upwards or downwards, i.e. the PE layer thickness can be e.g. 40 μm±10 or 20%, but also larger.

The weakening produced as predetermined breaking point 2 under the action of light can have a depth 11 advantageously down to the surface of the barrier layer 9 as thereby the pressure application for opening the film bag wall 7 is lowest while the function of the barrier layer 9 is not or only insignificantly affected. The predetermined breaking point 2, however, can also be produced by other methods, for example by scratching.

When the predetermined breaking point 2 is produced, the integrity at least of the lowermost barrier layer 9 can be ensured by means of an Nd:YAG or CO2 laser light source.

FIG. 1 d shows a view as a plan view of the predetermined breaking point 2 produced by the action of light in different exemplary shapes 13 a. For the selection of the different shapes 13 a, it is advantageous for the greatest weakening to start from the center 14 of the predetermined breaking point 2, so that a uniform bulge 30 is produced and thus a uniform outward shape 13 can be achieved when the film bag 1 is opened starting from the predetermined breaking point 2, and the jet angle of the product 41 can be influenced. However, predetermined breaking points whose maximum weakening does not start from the center 14 of the predetermined breaking point 2 and other forms can also be used. However, the star shape 13 is a preferred predetermined breaking point shape.

FIG. 2 shows a three-dimensional view of an exemplary cover 15 by which a predetermined breaking point 2 of a film bag 1 can be covered. The size of the cover 15 of the predetermined breaking point 2 can be governed, for example, by the cross-sectional area of the draining chamber 24, so that during transport and handling by the operator/a machine, the points in the draining chamber that come into contact with the product remain hygienic and clean. Here, germ contamination of the product 33 by microorganisms during the draining of the film bag 1 can be prevented. The cover 15 on the film bag 1 can be fixed, for example, by means of an adhesive and additionally comprise, for facilitating handling by the operator/a machine for removing the cover from the bag wall, a cover tongue 16 which is not fixed to the film bag wall by means of an adhesive but can be lifted off, so that by gripping the cover tongue 16 and pulling it, the cover 15 can be detached.

FIG. 3 a shows a side view as a section of an exemplary draining device 17 with a film bag 1 inserted in the draining chamber 24 and the pressing device 18 resting on it/against it. The exemplary positioning of the film bag 1 causes an air bubble 34 to be located at the film bag wall opposite the predetermined breaking point. The draining chamber 24 can have at least one outlet opening 36 which can be joined by a product chamber 32. The pressing device 18 can additionally comprise a compressible cushion 21. Equally, the draining chamber 24 can have a flush connection 39 via which the product chamber 32 or parts of the draining chamber 24 and parts of the film bag 1 can be flushed, for example, with mixing water (still or blended with CO2).

FIG. 3 b shows a side view as a section of an exemplary draining device 17 in the snapshot of a draining process step of the inserted film bag 1.

By the pressing action of the pressing device 18, the container wall 7 can expand into the outlet opening 36 of the draining chamber 24 and a bulge 30 can be formed in the process which leads to the elongation at break of the predetermined breaking point 2 being exceeded and opens the film bag 1, so that the product 33 can flow out of the film bag. Advantageously, the pressing action of the pressing device can be slowly increased, for example from 0−200 kPa, or from 0-500 kPa or more in 5-30 s, or within 1-100 s, e.g. to be able to achieve a better splashing behavior, for example by restricting the product jet angle 41 to less than 180° of the product exiting from the film bag 1.

The draining device 17 can be designed such that the pressing device 18 can be positioned in a controlled manner. In the process, the position of the pressing device 18 is adjusted by suited means, where this positioning can be effected independent of whether a film bag 1 is present or not. The pressing device 18 is moved, for example, at a preset and continuously variable speed, this being done independent of whether a film bag 1 is present or not. The preset speed can be, for example 0.1, 0.5, 1.0, 2.0, 5.0, 10, 20 or 40 mm per minute or more. The preset speed can also be below one of these values.

Pressure variations of 0.0−200 kPa or 0.0−500 kPa can be achieved here, for example, in 5-30 s or within 1-100 s. This can help to achieve a controlled pressure build-up in the film bag 1, and thus a sudden or uncontrolled lowering of the pressing device 18, accompanied by an undesired sudden opening of the container, can be prevented. For this, the pressing device 18 is moved, for example, hydraulically or electromotively, where by a defined flow rate of hydraulic pressurizing/propellant agent into a hydraulic cylinder or motor provided for moving the pressing device 18, or by a defined rate of motion of a motor (for example an electric motor, such as a stepper or asynchronous motor), the speed of motion of the pressing device 18 is defined. The control or pressurization of the pressing device 18 can also be effected, for example, by means of a threaded spindle which is driven, as explained above, by an electric motor or hydraulically.

A minimum speed of, for example, 0.05, 0.10, 1.00 or 20 mm per minute is required to achieve a controlled draining of the film bag, a speed below a maximum speed of, for example, 100, 200 or 500 mm per minute ensures a slow and controlled opening of the film bag 1.

The pressing device 18 can have a compressible cushion 22 which can, when the pressing device is lowered/presses, expand into the bulge 23 formed in the process, as in the region of the outlet opening 36 of the draining chamber 32, no resistance builds up, and it can in this manner press out product residues in the film bag 1, in particular in the bulge 31 of the predetermined breaking point 2 of the already largely drained film bag.

FIG. 3 c shows a side view as a section of an exemplary draining device 17 in the snapshot of a flushing process with mixing water/mixing agent. Via the flush water inlet 39, the bulge 30 of the film bag 1 and the outward shape of the predetermined breaking point 2 of the film bag, parts of the draining chamber 24 and the product chamber 32 are flushed, for example with water 44 blended with CO2, so that nearly no product residues are left. So, the product and the flush-out agent can be found e.g. as mixed drink in the mixing tank 43.

FIG. 4 shows a three-dimensional view of a nearly completely drained film bag 1 which by way of example has a uniform outward shape 31 around the center 14 of the predetermined breaking point 2 which was produced by stretching along during the formation of the bulge 30 of the film bag wall 7 by the pressing operation/pressurization.

FIG. 5 shows a side view as a section of an exemplary device 17 for draining the film bag 1. The draining device 17 preferably consists of a draining chamber 24 of which the geometrical dimensions can be adapted to the size of the container 1 as to its length 3 b and width 3 c, so that a container 1 filled with product can be inserted into the draining chamber 24 nearly without any gaps. Here, the surrounding distance 26 of the pressing device 18 to the internal wall 25 can be between 0.01 mm and 20 mm, but is preferably 1±0.5 mm. One can thereby avoid that the container is pressed into and/or gets clamped in the distance 26 between the draining chamber 24 and the pressing device 18 during pressing. The shape of the draining chamber 24 can be, for example, rectangular or square, where the draining chamber 24 can, for example, form a pan whose side wall design or internal wall 25, respectively, can be higher than the flatly inserted container 1 filled with product.

The draining device 17 can comprise a pressing device 18, for example with a pressure plate or plunger 18 a, whose geometrical dimensions can be somewhat smaller than the surrounding internal wall 25 of the draining chamber 24, but which can preferably be inserted into the draining chamber 24 with an accurate fit.

Pressure can be exerted onto the container 1 inserted in the draining chamber 24 via the pressing device 18. Here, the container 1 can bulge into the product outlet opening 36 of the draining chamber 32 until the predetermined breaking point 2 opens and drains the container. The drive of the pressing device 18 is designed, for example, hydraulically or electronically, as described above with respect to FIG. 3 b.

The pressing device 18 can include a compressible cushion 21 at its bottom side, for example an air cushion or an elastomer, via which pressure can be exerted onto the film bag 1. In the process, the compressible cushion 21 can image the container's contour, and thus a uniform pressure distribution onto the container 1 and onto possible weld seams and pleats of the container can be achieved.

The draining chamber 24 can include an opening 36 for the product outlet which is located, for example, centrically in the bottom 27 of the draining chamber. However, several openings are also possible.

When pressure is exerted onto the inserted container 1 filled with product with a pressing device 18 with a compressible cushion 21, the cushion can expand into the product outlet opening 36 of the draining chamber 24 and thus better drain the container.

A product chamber 32 whose volume 35 can, for example, receive the complete product 33 that can be located in the film bag 1, can follow the opening 36. The product chamber 32 can additionally comprise a product chamber outlet opening 38, for example in the vertical extension of the product chamber 32 or, for example downwards in the direction of gravity, where the outlet opening 38 can have a smaller cross-section than the product chamber 32; for example, the outlet opening 38 can have a cross-section which is by 1% to 90% smaller than the cross-section of the product chamber 32 to be able to effect a product back-up 42. For example, a width of the product chamber of e.g. 30 mm diameter and an outlet opening of e.g. 6 mm are preferred. The design of the product chamber outlet opening 38 can extend, for example, conically in the direction of gravity.

The opening 35 of the product chamber can moreover comprise an inlet 40 to a flush connection 39, for example directly underneath the draining chamber 24. Preferably, the inlet 40 can be designed, for example, tangentially. After the container 1 has been drained, mixing water 44, for example blended with CO2, can be supplied to the product chamber 32 and/or the region directly underneath the draining chamber product outlet opening 36 via the flush connection 39 and the inlet 40, and the product chamber 32 can be flushed in this way.

Moreover, a mixing tank 43 for receiving the product 33 and/or mixing/flushing water 44 can be located underneath the outlet opening 38.

The reference numerals used herein are as follows:

-   1 Film bag/multilayer film bag -   2 Predetermined breaking point -   2 a Position detection of the film bag -   3 a Height of the film bag -   3 b Length of the film bag -   3 c Width of the film bag -   4 Diagonal positioning -   5 Center of the film bag -   6 Bottom side of the film bag -   7 Wall of the film bag/bag wall -   8 Inner wall layer of the bag wall -   9 Barrier layer of the bag wall -   10 External wall layer of the bag wall -   11 Depth of the predetermined breaking point -   12 Width of the predetermined breaking point -   13 Star-shaped predetermined breaking point -   13 a Different predetermined breaking point shapes -   14 Center of the predetermined breaking point -   15 Cover of the predetermined breaking point -   16 Cover tongue -   17 Draining device for a film bag -   18 Pressing device for draining the film bag -   18 a Plunger/pressure plate of the pressing device -   19 Dimension of the pressing device -   20 Outer edge of the pressing device -   21 Cushion of the pressing device -   22 Compression of the cushion -   23 Bulge of the compressed cushion -   24 Draining chamber -   25 Internal wall of the draining chamber -   26 Distance between the draining chamber wall and the pressing     device -   27 Bottom of the draining chamber -   28 Sealing of the container on the bottom of the draining chamber -   29 Empty film bag -   30 Bulge of the empty or largely empty film bag and/or bulge of the     film bag before the predetermined breaking point is opened -   31 Outward shape of the predetermined breaking point of the empty or     largely empty film bag -   32 Product chamber of draining device -   33 Product in the film bag -   34 Air bubble in the film bag -   35 Volume of the product chamber -   36 Outlet opening of the draining chamber -   38 Outlet opening of the product chamber -   39 Flush connection of the product chamber -   40 Tangential inlet from the flush connection -   41 Jet angle of product during draining of the film bag -   42 Product back-up in the product chamber -   43 Mixing tank 

1. A multilayer film bag for storing food products with a bag wall comprising at least one external wall, one barrier layer, and one internal wall wherein the multilayer film bag comprises a predetermined breaking point in the bag wall which tears open under pressure without any parts of the film bag tearing off.
 2. A film bag according to claim 1, wherein the predetermined breaking point is located on an external wall side of the film bag.
 3. A film bag according to claim 2, wherein an extension of the predetermined breaking point is smaller than one half, one third, or one fourth of the extension of the external wall side on which the predetermined breaking point is located.
 4. A film bag according to claim 1, wherein the film bag comprises a weld seam at least on one side, the weld seam withstanding pressures that are above a pressure range leading to an opening of the predetermined breaking point.
 5. A film bag according to claim 1, wherein the predetermined breaking point comprises a cover against contamination, wherein the cover is fixed by means of an adhesive and comprises a cover tongue by which the cover can be removed manually or mechanically.
 6. A film bag according to claim 1, wherein the predetermined breaking point is produced by the action of light.
 7. A film bag according to claim 1, wherein a depth of the predetermined breaking point in the external wall of the film bag does not reach deeper than to the barrier layer.
 8. A film bag according to claim 1, wherein the film bag has dimensions including a height, a length, and a width, wherein the height is smaller than the length and the width.
 9. A film bag according to claim 1, wherein the film bag comprises a position detection mark.
 10. A film bag according to claim 1, wherein the predetermined breaking point bulges to an outside of the film bag under the action of the pressure before the wall is torn open and forms a bulge.
 11. A method of draining the film bag of claim 1 largely without leaving any residues, comprising the steps of: placing the film bag into a draining chamber, the draining chamber having geometrical dimensions including a draining chamber length and a draining chamber width adapted to a film bag width and a film bag height; exerting pressure onto the film bag by means of a pressing device, so that a bulge is formed which, when the film bag wall is overexpanded on the side of the predetermined breaking point, opens the predetermined breaking point; and draining the film bag largely without leaving any residues.
 12. A method according to claim 11, wherein uniform pressure is produced onto the surface of the film bag by a cushion attached to the bottom side of the pressing device and which is compressed under pressurization.
 13. A method according to claim 12, wherein the cushion is compressed when pressure is exerted onto the drained film bag on the bottom of the draining chamber, the cushion being pressed into an outlet opening of the draining chamber and pressing the residual quantity of film bag contents through the bulge of the film bag wall from the predetermined breaking point out of the film bag and nearly completely draining the film bag.
 14. A method according to claim 11, wherein an air bubble in the film bag is located at the uppermost region of the bag's height in a draining position and flushes the residues of film bag contents out of the film bag during draining.
 15. A method according to claim 11, wherein the film bag is drained into a product chamber and further comprising the step of flushing the product chamber with mixing water after the film bag has been drained.
 16. A device for draining a film bag according to claim 1 filled with product, the device comprising a draining chamber with at least one outlet opening and at least one pressing device, wherein the pressing device can be moved at a predefined speed and is preconfigured such that pressurization can be achieved which leads to an opening of the predetermined breaking point of the film bag and to a draining of the filled film bag.
 17. A device according to claim 16, wherein the pressing device is configured such that it can be moved at a predefined speed of or above 0.1, 0.5, 1.0, 2.0, 5.0, 10, 20 or 40 mm per minute.
 18. A device according to claim 16 wherein a bottom side of the pressing device comprises a plunger with a compressible cushion.
 19. A device according to claim 16 wherein a surrounding distance between the pressing device and an internal wall of the draining chamber is between 0.01 mm and 20 mm.
 20. A film bag according to claim 1, wherein the food products comprise beverage concentrates.
 21. A film bag according to claim 1, wherein the barrier layer provides a barrier for oxygen or light.
 22. A film bag according to claim 1, wherein the film bag wall tears open at pressures above 100 kPa, 150 kPa, 200 kPa, 400 kPa or 500 kPa, without any parts of the film bag tearing off.
 23. A film bag according to claim 2, wherein the predetermined breaking point is positioned centered on the external wall side.
 24. A method according to claim 11, wherein the bulge opens the predetermined breaking point in the center of the predetermined breaking point.
 25. A method according to claim 11, wherein the pressing device is moved at a predefined speed for exerting the pressure onto the film bag.
 26. A method according to claim 14, wherein the mixing water is still or blended with CO₂.
 27. A device according to claim 17, wherein the pressing device is configured such that it can be moved at a continuously variable speed.
 28. A device according to claim 16, wherein the pressing device is configured such that pressure variations of 0.0 to 200 or 500 kPa can be reached within 5 to 30 s or within 1 to 100 s.
 29. A device according to claim 16, wherein the pressing device is configured such that a pressure exertion on the film bag of more than 50 kPa, 100 kPa, 200 kPa, 400 kPa or 500 kPa can be achieved.
 30. A device according to claim 18 wherein the compressible cushion comprises an elastomer cushion or an air cushion.
 31. A device according to claim 19, wherein the surrounding distance between the pressing device and the internal wall is 1 mm.
 32. A film bag according to claim 4, wherein the film bag has a rectangular shape. 